Such an actuating device is known from the PCT Publication No. WO 89/01322. The actuating device disclosed in that document is designed as a four-point or four-lever articulation, two levers of the device being linked to the end of the actuating lever which is distant from the apparatus housing. The transmission of the motion to the said apparatus part to be actuated, for example a ram, is effected via a steering lever which necessitates a correspondingly strong execution of this lever. The purpose of that construction is essentially to have the strongest fingers of the actuating hand applied at the free end of the actuating lever which faces the apparatus housing in order to exert an increased force. That construction is heavy, and there is an increased risk of soiling, on one hand, and the risk of catching a finger, the ball of the thumb or a glove during actuating between the widely protruding levers, on the other hand. Furthermore, the protruding of the lever system leads to the effect that the upper fingers exert a torque and traction and pressure forces on several axles which causes an increased friction.